xref: /openbmc/linux/fs/gfs2/glops.c (revision d6b412c5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
4  * Copyright (C) 2004-2008 Red Hat, Inc.  All rights reserved.
5  */
6 
7 #include <linux/spinlock.h>
8 #include <linux/completion.h>
9 #include <linux/buffer_head.h>
10 #include <linux/gfs2_ondisk.h>
11 #include <linux/bio.h>
12 #include <linux/posix_acl.h>
13 #include <linux/security.h>
14 
15 #include "gfs2.h"
16 #include "incore.h"
17 #include "bmap.h"
18 #include "glock.h"
19 #include "glops.h"
20 #include "inode.h"
21 #include "log.h"
22 #include "meta_io.h"
23 #include "recovery.h"
24 #include "rgrp.h"
25 #include "util.h"
26 #include "trans.h"
27 #include "dir.h"
28 #include "lops.h"
29 
30 struct workqueue_struct *gfs2_freeze_wq;
31 
32 extern struct workqueue_struct *gfs2_control_wq;
33 
gfs2_ail_error(struct gfs2_glock * gl,const struct buffer_head * bh)34 static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
35 {
36 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
37 
38 	fs_err(sdp,
39 	       "AIL buffer %p: blocknr %llu state 0x%08lx mapping %p page "
40 	       "state 0x%lx\n",
41 	       bh, (unsigned long long)bh->b_blocknr, bh->b_state,
42 	       bh->b_folio->mapping, bh->b_folio->flags);
43 	fs_err(sdp, "AIL glock %u:%llu mapping %p\n",
44 	       gl->gl_name.ln_type, gl->gl_name.ln_number,
45 	       gfs2_glock2aspace(gl));
46 	gfs2_lm(sdp, "AIL error\n");
47 	gfs2_withdraw_delayed(sdp);
48 }
49 
50 /**
51  * __gfs2_ail_flush - remove all buffers for a given lock from the AIL
52  * @gl: the glock
53  * @fsync: set when called from fsync (not all buffers will be clean)
54  * @nr_revokes: Number of buffers to revoke
55  *
56  * None of the buffers should be dirty, locked, or pinned.
57  */
58 
__gfs2_ail_flush(struct gfs2_glock * gl,bool fsync,unsigned int nr_revokes)59 static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
60 			     unsigned int nr_revokes)
61 {
62 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
63 	struct list_head *head = &gl->gl_ail_list;
64 	struct gfs2_bufdata *bd, *tmp;
65 	struct buffer_head *bh;
66 	const unsigned long b_state = (1UL << BH_Dirty)|(1UL << BH_Pinned)|(1UL << BH_Lock);
67 
68 	gfs2_log_lock(sdp);
69 	spin_lock(&sdp->sd_ail_lock);
70 	list_for_each_entry_safe_reverse(bd, tmp, head, bd_ail_gl_list) {
71 		if (nr_revokes == 0)
72 			break;
73 		bh = bd->bd_bh;
74 		if (bh->b_state & b_state) {
75 			if (fsync)
76 				continue;
77 			gfs2_ail_error(gl, bh);
78 		}
79 		gfs2_trans_add_revoke(sdp, bd);
80 		nr_revokes--;
81 	}
82 	GLOCK_BUG_ON(gl, !fsync && atomic_read(&gl->gl_ail_count));
83 	spin_unlock(&sdp->sd_ail_lock);
84 	gfs2_log_unlock(sdp);
85 
86 	if (gfs2_withdrawing(sdp))
87 		gfs2_withdraw(sdp);
88 }
89 
90 
gfs2_ail_empty_gl(struct gfs2_glock * gl)91 static int gfs2_ail_empty_gl(struct gfs2_glock *gl)
92 {
93 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
94 	struct gfs2_trans tr;
95 	unsigned int revokes;
96 	int ret = 0;
97 
98 	revokes = atomic_read(&gl->gl_ail_count);
99 
100 	if (!revokes) {
101 		bool have_revokes;
102 		bool log_in_flight;
103 
104 		/*
105 		 * We have nothing on the ail, but there could be revokes on
106 		 * the sdp revoke queue, in which case, we still want to flush
107 		 * the log and wait for it to finish.
108 		 *
109 		 * If the sdp revoke list is empty too, we might still have an
110 		 * io outstanding for writing revokes, so we should wait for
111 		 * it before returning.
112 		 *
113 		 * If none of these conditions are true, our revokes are all
114 		 * flushed and we can return.
115 		 */
116 		gfs2_log_lock(sdp);
117 		have_revokes = !list_empty(&sdp->sd_log_revokes);
118 		log_in_flight = atomic_read(&sdp->sd_log_in_flight);
119 		gfs2_log_unlock(sdp);
120 		if (have_revokes)
121 			goto flush;
122 		if (log_in_flight)
123 			log_flush_wait(sdp);
124 		return 0;
125 	}
126 
127 	memset(&tr, 0, sizeof(tr));
128 	set_bit(TR_ONSTACK, &tr.tr_flags);
129 	ret = __gfs2_trans_begin(&tr, sdp, 0, revokes, _RET_IP_);
130 	if (ret) {
131 		fs_err(sdp, "Transaction error %d: Unable to write revokes.", ret);
132 		goto flush;
133 	}
134 	__gfs2_ail_flush(gl, 0, revokes);
135 	gfs2_trans_end(sdp);
136 
137 flush:
138 	if (!ret)
139 		gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
140 				GFS2_LFC_AIL_EMPTY_GL);
141 	return ret;
142 }
143 
gfs2_ail_flush(struct gfs2_glock * gl,bool fsync)144 void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
145 {
146 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
147 	unsigned int revokes = atomic_read(&gl->gl_ail_count);
148 	int ret;
149 
150 	if (!revokes)
151 		return;
152 
153 	ret = gfs2_trans_begin(sdp, 0, revokes);
154 	if (ret)
155 		return;
156 	__gfs2_ail_flush(gl, fsync, revokes);
157 	gfs2_trans_end(sdp);
158 	gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_NORMAL |
159 		       GFS2_LFC_AIL_FLUSH);
160 }
161 
162 /**
163  * gfs2_rgrp_metasync - sync out the metadata of a resource group
164  * @gl: the glock protecting the resource group
165  *
166  */
167 
gfs2_rgrp_metasync(struct gfs2_glock * gl)168 static int gfs2_rgrp_metasync(struct gfs2_glock *gl)
169 {
170 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
171 	struct address_space *metamapping = &sdp->sd_aspace;
172 	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
173 	const unsigned bsize = sdp->sd_sb.sb_bsize;
174 	loff_t start = (rgd->rd_addr * bsize) & PAGE_MASK;
175 	loff_t end = PAGE_ALIGN((rgd->rd_addr + rgd->rd_length) * bsize) - 1;
176 	int error;
177 
178 	filemap_fdatawrite_range(metamapping, start, end);
179 	error = filemap_fdatawait_range(metamapping, start, end);
180 	WARN_ON_ONCE(error && !gfs2_withdrawing_or_withdrawn(sdp));
181 	mapping_set_error(metamapping, error);
182 	if (error)
183 		gfs2_io_error(sdp);
184 	return error;
185 }
186 
187 /**
188  * rgrp_go_sync - sync out the metadata for this glock
189  * @gl: the glock
190  *
191  * Called when demoting or unlocking an EX glock.  We must flush
192  * to disk all dirty buffers/pages relating to this glock, and must not
193  * return to caller to demote/unlock the glock until I/O is complete.
194  */
195 
rgrp_go_sync(struct gfs2_glock * gl)196 static int rgrp_go_sync(struct gfs2_glock *gl)
197 {
198 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
199 	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
200 	int error;
201 
202 	if (!rgd || !test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
203 		return 0;
204 	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
205 
206 	gfs2_log_flush(sdp, gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
207 		       GFS2_LFC_RGRP_GO_SYNC);
208 	error = gfs2_rgrp_metasync(gl);
209 	if (!error)
210 		error = gfs2_ail_empty_gl(gl);
211 	gfs2_free_clones(rgd);
212 	return error;
213 }
214 
215 /**
216  * rgrp_go_inval - invalidate the metadata for this glock
217  * @gl: the glock
218  * @flags:
219  *
220  * We never used LM_ST_DEFERRED with resource groups, so that we
221  * should always see the metadata flag set here.
222  *
223  */
224 
rgrp_go_inval(struct gfs2_glock * gl,int flags)225 static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
226 {
227 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
228 	struct address_space *mapping = &sdp->sd_aspace;
229 	struct gfs2_rgrpd *rgd = gfs2_glock2rgrp(gl);
230 	const unsigned bsize = sdp->sd_sb.sb_bsize;
231 	loff_t start, end;
232 
233 	if (!rgd)
234 		return;
235 	start = (rgd->rd_addr * bsize) & PAGE_MASK;
236 	end = PAGE_ALIGN((rgd->rd_addr + rgd->rd_length) * bsize) - 1;
237 	gfs2_rgrp_brelse(rgd);
238 	WARN_ON_ONCE(!(flags & DIO_METADATA));
239 	truncate_inode_pages_range(mapping, start, end);
240 }
241 
gfs2_rgrp_go_dump(struct seq_file * seq,const struct gfs2_glock * gl,const char * fs_id_buf)242 static void gfs2_rgrp_go_dump(struct seq_file *seq, const struct gfs2_glock *gl,
243 			      const char *fs_id_buf)
244 {
245 	struct gfs2_rgrpd *rgd = gl->gl_object;
246 
247 	if (rgd)
248 		gfs2_rgrp_dump(seq, rgd, fs_id_buf);
249 }
250 
gfs2_glock2inode(struct gfs2_glock * gl)251 static struct gfs2_inode *gfs2_glock2inode(struct gfs2_glock *gl)
252 {
253 	struct gfs2_inode *ip;
254 
255 	spin_lock(&gl->gl_lockref.lock);
256 	ip = gl->gl_object;
257 	if (ip)
258 		set_bit(GIF_GLOP_PENDING, &ip->i_flags);
259 	spin_unlock(&gl->gl_lockref.lock);
260 	return ip;
261 }
262 
gfs2_glock2rgrp(struct gfs2_glock * gl)263 struct gfs2_rgrpd *gfs2_glock2rgrp(struct gfs2_glock *gl)
264 {
265 	struct gfs2_rgrpd *rgd;
266 
267 	spin_lock(&gl->gl_lockref.lock);
268 	rgd = gl->gl_object;
269 	spin_unlock(&gl->gl_lockref.lock);
270 
271 	return rgd;
272 }
273 
gfs2_clear_glop_pending(struct gfs2_inode * ip)274 static void gfs2_clear_glop_pending(struct gfs2_inode *ip)
275 {
276 	if (!ip)
277 		return;
278 
279 	clear_bit_unlock(GIF_GLOP_PENDING, &ip->i_flags);
280 	wake_up_bit(&ip->i_flags, GIF_GLOP_PENDING);
281 }
282 
283 /**
284  * gfs2_inode_metasync - sync out the metadata of an inode
285  * @gl: the glock protecting the inode
286  *
287  */
gfs2_inode_metasync(struct gfs2_glock * gl)288 int gfs2_inode_metasync(struct gfs2_glock *gl)
289 {
290 	struct address_space *metamapping = gfs2_glock2aspace(gl);
291 	int error;
292 
293 	filemap_fdatawrite(metamapping);
294 	error = filemap_fdatawait(metamapping);
295 	if (error)
296 		gfs2_io_error(gl->gl_name.ln_sbd);
297 	return error;
298 }
299 
300 /**
301  * inode_go_sync - Sync the dirty metadata of an inode
302  * @gl: the glock protecting the inode
303  *
304  */
305 
inode_go_sync(struct gfs2_glock * gl)306 static int inode_go_sync(struct gfs2_glock *gl)
307 {
308 	struct gfs2_inode *ip = gfs2_glock2inode(gl);
309 	int isreg = ip && S_ISREG(ip->i_inode.i_mode);
310 	struct address_space *metamapping = gfs2_glock2aspace(gl);
311 	int error = 0, ret;
312 
313 	if (isreg) {
314 		if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
315 			unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
316 		inode_dio_wait(&ip->i_inode);
317 	}
318 	if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
319 		goto out;
320 
321 	GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_EXCLUSIVE);
322 
323 	gfs2_log_flush(gl->gl_name.ln_sbd, gl, GFS2_LOG_HEAD_FLUSH_NORMAL |
324 		       GFS2_LFC_INODE_GO_SYNC);
325 	filemap_fdatawrite(metamapping);
326 	if (isreg) {
327 		struct address_space *mapping = ip->i_inode.i_mapping;
328 		filemap_fdatawrite(mapping);
329 		error = filemap_fdatawait(mapping);
330 		mapping_set_error(mapping, error);
331 	}
332 	ret = gfs2_inode_metasync(gl);
333 	if (!error)
334 		error = ret;
335 	ret = gfs2_ail_empty_gl(gl);
336 	if (!error)
337 		error = ret;
338 	/*
339 	 * Writeback of the data mapping may cause the dirty flag to be set
340 	 * so we have to clear it again here.
341 	 */
342 	smp_mb__before_atomic();
343 	clear_bit(GLF_DIRTY, &gl->gl_flags);
344 
345 out:
346 	gfs2_clear_glop_pending(ip);
347 	return error;
348 }
349 
350 /**
351  * inode_go_inval - prepare a inode glock to be released
352  * @gl: the glock
353  * @flags:
354  *
355  * Normally we invalidate everything, but if we are moving into
356  * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
357  * can keep hold of the metadata, since it won't have changed.
358  *
359  */
360 
inode_go_inval(struct gfs2_glock * gl,int flags)361 static void inode_go_inval(struct gfs2_glock *gl, int flags)
362 {
363 	struct gfs2_inode *ip = gfs2_glock2inode(gl);
364 
365 	if (flags & DIO_METADATA) {
366 		struct address_space *mapping = gfs2_glock2aspace(gl);
367 		truncate_inode_pages(mapping, 0);
368 		if (ip) {
369 			set_bit(GLF_INSTANTIATE_NEEDED, &gl->gl_flags);
370 			forget_all_cached_acls(&ip->i_inode);
371 			security_inode_invalidate_secctx(&ip->i_inode);
372 			gfs2_dir_hash_inval(ip);
373 		}
374 	}
375 
376 	if (ip == GFS2_I(gl->gl_name.ln_sbd->sd_rindex)) {
377 		gfs2_log_flush(gl->gl_name.ln_sbd, NULL,
378 			       GFS2_LOG_HEAD_FLUSH_NORMAL |
379 			       GFS2_LFC_INODE_GO_INVAL);
380 		gl->gl_name.ln_sbd->sd_rindex_uptodate = 0;
381 	}
382 	if (ip && S_ISREG(ip->i_inode.i_mode))
383 		truncate_inode_pages(ip->i_inode.i_mapping, 0);
384 
385 	gfs2_clear_glop_pending(ip);
386 }
387 
388 /**
389  * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
390  * @gl: the glock
391  *
392  * Returns: 1 if it's ok
393  */
394 
inode_go_demote_ok(const struct gfs2_glock * gl)395 static int inode_go_demote_ok(const struct gfs2_glock *gl)
396 {
397 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
398 
399 	if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
400 		return 0;
401 
402 	return 1;
403 }
404 
gfs2_dinode_in(struct gfs2_inode * ip,const void * buf)405 static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
406 {
407 	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
408 	const struct gfs2_dinode *str = buf;
409 	struct timespec64 atime;
410 	u16 height, depth;
411 	umode_t mode = be32_to_cpu(str->di_mode);
412 	struct inode *inode = &ip->i_inode;
413 	bool is_new = inode->i_state & I_NEW;
414 
415 	if (unlikely(ip->i_no_addr != be64_to_cpu(str->di_num.no_addr)))
416 		goto corrupt;
417 	if (unlikely(!is_new && inode_wrong_type(inode, mode)))
418 		goto corrupt;
419 	ip->i_no_formal_ino = be64_to_cpu(str->di_num.no_formal_ino);
420 	inode->i_mode = mode;
421 	if (is_new) {
422 		inode->i_rdev = 0;
423 		switch (mode & S_IFMT) {
424 		case S_IFBLK:
425 		case S_IFCHR:
426 			inode->i_rdev = MKDEV(be32_to_cpu(str->di_major),
427 					      be32_to_cpu(str->di_minor));
428 			break;
429 		}
430 	}
431 
432 	i_uid_write(inode, be32_to_cpu(str->di_uid));
433 	i_gid_write(inode, be32_to_cpu(str->di_gid));
434 	set_nlink(inode, be32_to_cpu(str->di_nlink));
435 	i_size_write(inode, be64_to_cpu(str->di_size));
436 	gfs2_set_inode_blocks(inode, be64_to_cpu(str->di_blocks));
437 	atime.tv_sec = be64_to_cpu(str->di_atime);
438 	atime.tv_nsec = be32_to_cpu(str->di_atime_nsec);
439 	if (timespec64_compare(&inode->i_atime, &atime) < 0)
440 		inode->i_atime = atime;
441 	inode->i_mtime.tv_sec = be64_to_cpu(str->di_mtime);
442 	inode->i_mtime.tv_nsec = be32_to_cpu(str->di_mtime_nsec);
443 	inode_set_ctime(inode, be64_to_cpu(str->di_ctime),
444 			be32_to_cpu(str->di_ctime_nsec));
445 
446 	ip->i_goal = be64_to_cpu(str->di_goal_meta);
447 	ip->i_generation = be64_to_cpu(str->di_generation);
448 
449 	ip->i_diskflags = be32_to_cpu(str->di_flags);
450 	ip->i_eattr = be64_to_cpu(str->di_eattr);
451 	/* i_diskflags and i_eattr must be set before gfs2_set_inode_flags() */
452 	gfs2_set_inode_flags(inode);
453 	height = be16_to_cpu(str->di_height);
454 	if (unlikely(height > sdp->sd_max_height))
455 		goto corrupt;
456 	ip->i_height = (u8)height;
457 
458 	depth = be16_to_cpu(str->di_depth);
459 	if (unlikely(depth > GFS2_DIR_MAX_DEPTH))
460 		goto corrupt;
461 	ip->i_depth = (u8)depth;
462 	ip->i_entries = be32_to_cpu(str->di_entries);
463 
464 	if (gfs2_is_stuffed(ip) && inode->i_size > gfs2_max_stuffed_size(ip))
465 		goto corrupt;
466 
467 	if (S_ISREG(inode->i_mode))
468 		gfs2_set_aops(inode);
469 
470 	return 0;
471 corrupt:
472 	gfs2_consist_inode(ip);
473 	return -EIO;
474 }
475 
476 /**
477  * gfs2_inode_refresh - Refresh the incore copy of the dinode
478  * @ip: The GFS2 inode
479  *
480  * Returns: errno
481  */
482 
gfs2_inode_refresh(struct gfs2_inode * ip)483 int gfs2_inode_refresh(struct gfs2_inode *ip)
484 {
485 	struct buffer_head *dibh;
486 	int error;
487 
488 	error = gfs2_meta_inode_buffer(ip, &dibh);
489 	if (error)
490 		return error;
491 
492 	error = gfs2_dinode_in(ip, dibh->b_data);
493 	brelse(dibh);
494 	return error;
495 }
496 
497 /**
498  * inode_go_instantiate - read in an inode if necessary
499  * @gh: The glock holder
500  *
501  * Returns: errno
502  */
503 
inode_go_instantiate(struct gfs2_glock * gl)504 static int inode_go_instantiate(struct gfs2_glock *gl)
505 {
506 	struct gfs2_inode *ip = gl->gl_object;
507 
508 	if (!ip) /* no inode to populate - read it in later */
509 		return 0;
510 
511 	return gfs2_inode_refresh(ip);
512 }
513 
inode_go_held(struct gfs2_holder * gh)514 static int inode_go_held(struct gfs2_holder *gh)
515 {
516 	struct gfs2_glock *gl = gh->gh_gl;
517 	struct gfs2_inode *ip = gl->gl_object;
518 	int error = 0;
519 
520 	if (!ip) /* no inode to populate - read it in later */
521 		return 0;
522 
523 	if (gh->gh_state != LM_ST_DEFERRED)
524 		inode_dio_wait(&ip->i_inode);
525 
526 	if ((ip->i_diskflags & GFS2_DIF_TRUNC_IN_PROG) &&
527 	    (gl->gl_state == LM_ST_EXCLUSIVE) &&
528 	    (gh->gh_state == LM_ST_EXCLUSIVE))
529 		error = gfs2_truncatei_resume(ip);
530 
531 	return error;
532 }
533 
534 /**
535  * inode_go_dump - print information about an inode
536  * @seq: The iterator
537  * @gl: The glock
538  * @fs_id_buf: file system id (may be empty)
539  *
540  */
541 
inode_go_dump(struct seq_file * seq,const struct gfs2_glock * gl,const char * fs_id_buf)542 static void inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl,
543 			  const char *fs_id_buf)
544 {
545 	struct gfs2_inode *ip = gl->gl_object;
546 	const struct inode *inode = &ip->i_inode;
547 
548 	if (ip == NULL)
549 		return;
550 
551 	gfs2_print_dbg(seq, "%s I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu "
552 		       "p:%lu\n", fs_id_buf,
553 		  (unsigned long long)ip->i_no_formal_ino,
554 		  (unsigned long long)ip->i_no_addr,
555 		  IF2DT(inode->i_mode), ip->i_flags,
556 		  (unsigned int)ip->i_diskflags,
557 		  (unsigned long long)i_size_read(inode),
558 		  inode->i_data.nrpages);
559 }
560 
561 /**
562  * freeze_go_callback - A cluster node is requesting a freeze
563  * @gl: the glock
564  * @remote: true if this came from a different cluster node
565  */
566 
freeze_go_callback(struct gfs2_glock * gl,bool remote)567 static void freeze_go_callback(struct gfs2_glock *gl, bool remote)
568 {
569 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
570 	struct super_block *sb = sdp->sd_vfs;
571 
572 	if (!remote ||
573 	    (gl->gl_state != LM_ST_SHARED &&
574 	     gl->gl_state != LM_ST_UNLOCKED) ||
575 	    gl->gl_demote_state != LM_ST_UNLOCKED)
576 		return;
577 
578 	/*
579 	 * Try to get an active super block reference to prevent racing with
580 	 * unmount (see super_trylock_shared()).  But note that unmount isn't
581 	 * the only place where a write lock on s_umount is taken, and we can
582 	 * fail here because of things like remount as well.
583 	 */
584 	if (down_read_trylock(&sb->s_umount)) {
585 		atomic_inc(&sb->s_active);
586 		up_read(&sb->s_umount);
587 		if (!queue_work(gfs2_freeze_wq, &sdp->sd_freeze_work))
588 			deactivate_super(sb);
589 	}
590 }
591 
592 /**
593  * freeze_go_xmote_bh - After promoting/demoting the freeze glock
594  * @gl: the glock
595  */
freeze_go_xmote_bh(struct gfs2_glock * gl)596 static int freeze_go_xmote_bh(struct gfs2_glock *gl)
597 {
598 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
599 	struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
600 	struct gfs2_glock *j_gl = ip->i_gl;
601 	struct gfs2_log_header_host head;
602 	int error;
603 
604 	if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
605 		j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
606 
607 		error = gfs2_find_jhead(sdp->sd_jdesc, &head, false);
608 		if (gfs2_assert_withdraw_delayed(sdp, !error))
609 			return error;
610 		if (gfs2_assert_withdraw_delayed(sdp, head.lh_flags &
611 						 GFS2_LOG_HEAD_UNMOUNT))
612 			return -EIO;
613 		sdp->sd_log_sequence = head.lh_sequence + 1;
614 		gfs2_log_pointers_init(sdp, head.lh_blkno);
615 	}
616 	return 0;
617 }
618 
619 /**
620  * freeze_go_demote_ok
621  * @gl: the glock
622  *
623  * Always returns 0
624  */
625 
freeze_go_demote_ok(const struct gfs2_glock * gl)626 static int freeze_go_demote_ok(const struct gfs2_glock *gl)
627 {
628 	return 0;
629 }
630 
631 /**
632  * iopen_go_callback - schedule the dcache entry for the inode to be deleted
633  * @gl: the glock
634  * @remote: true if this came from a different cluster node
635  *
636  * gl_lockref.lock lock is held while calling this
637  */
iopen_go_callback(struct gfs2_glock * gl,bool remote)638 static void iopen_go_callback(struct gfs2_glock *gl, bool remote)
639 {
640 	struct gfs2_inode *ip = gl->gl_object;
641 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
642 
643 	if (!remote || sb_rdonly(sdp->sd_vfs) ||
644 	    test_bit(SDF_KILL, &sdp->sd_flags))
645 		return;
646 
647 	if (gl->gl_demote_state == LM_ST_UNLOCKED &&
648 	    gl->gl_state == LM_ST_SHARED && ip) {
649 		gl->gl_lockref.count++;
650 		if (!gfs2_queue_try_to_evict(gl))
651 			gl->gl_lockref.count--;
652 	}
653 }
654 
655 /**
656  * inode_go_free - wake up anyone waiting for dlm's unlock ast to free it
657  * @gl: glock being freed
658  *
659  * For now, this is only used for the journal inode glock. In withdraw
660  * situations, we need to wait for the glock to be freed so that we know
661  * other nodes may proceed with recovery / journal replay.
662  */
inode_go_free(struct gfs2_glock * gl)663 static void inode_go_free(struct gfs2_glock *gl)
664 {
665 	/* Note that we cannot reference gl_object because it's already set
666 	 * to NULL by this point in its lifecycle. */
667 	if (!test_bit(GLF_FREEING, &gl->gl_flags))
668 		return;
669 	clear_bit_unlock(GLF_FREEING, &gl->gl_flags);
670 	wake_up_bit(&gl->gl_flags, GLF_FREEING);
671 }
672 
673 /**
674  * nondisk_go_callback - used to signal when a node did a withdraw
675  * @gl: the nondisk glock
676  * @remote: true if this came from a different cluster node
677  *
678  */
nondisk_go_callback(struct gfs2_glock * gl,bool remote)679 static void nondisk_go_callback(struct gfs2_glock *gl, bool remote)
680 {
681 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
682 
683 	/* Ignore the callback unless it's from another node, and it's the
684 	   live lock. */
685 	if (!remote || gl->gl_name.ln_number != GFS2_LIVE_LOCK)
686 		return;
687 
688 	/* First order of business is to cancel the demote request. We don't
689 	 * really want to demote a nondisk glock. At best it's just to inform
690 	 * us of another node's withdraw. We'll keep it in SH mode. */
691 	clear_bit(GLF_DEMOTE, &gl->gl_flags);
692 	clear_bit(GLF_PENDING_DEMOTE, &gl->gl_flags);
693 
694 	/* Ignore the unlock if we're withdrawn, unmounting, or in recovery. */
695 	if (test_bit(SDF_NORECOVERY, &sdp->sd_flags) ||
696 	    test_bit(SDF_WITHDRAWN, &sdp->sd_flags) ||
697 	    test_bit(SDF_REMOTE_WITHDRAW, &sdp->sd_flags))
698 		return;
699 
700 	/* We only care when a node wants us to unlock, because that means
701 	 * they want a journal recovered. */
702 	if (gl->gl_demote_state != LM_ST_UNLOCKED)
703 		return;
704 
705 	if (sdp->sd_args.ar_spectator) {
706 		fs_warn(sdp, "Spectator node cannot recover journals.\n");
707 		return;
708 	}
709 
710 	fs_warn(sdp, "Some node has withdrawn; checking for recovery.\n");
711 	set_bit(SDF_REMOTE_WITHDRAW, &sdp->sd_flags);
712 	/*
713 	 * We can't call remote_withdraw directly here or gfs2_recover_journal
714 	 * because this is called from the glock unlock function and the
715 	 * remote_withdraw needs to enqueue and dequeue the same "live" glock
716 	 * we were called from. So we queue it to the control work queue in
717 	 * lock_dlm.
718 	 */
719 	queue_delayed_work(gfs2_control_wq, &sdp->sd_control_work, 0);
720 }
721 
722 const struct gfs2_glock_operations gfs2_meta_glops = {
723 	.go_type = LM_TYPE_META,
724 	.go_flags = GLOF_NONDISK,
725 };
726 
727 const struct gfs2_glock_operations gfs2_inode_glops = {
728 	.go_sync = inode_go_sync,
729 	.go_inval = inode_go_inval,
730 	.go_demote_ok = inode_go_demote_ok,
731 	.go_instantiate = inode_go_instantiate,
732 	.go_held = inode_go_held,
733 	.go_dump = inode_go_dump,
734 	.go_type = LM_TYPE_INODE,
735 	.go_flags = GLOF_ASPACE | GLOF_LRU | GLOF_LVB,
736 	.go_free = inode_go_free,
737 };
738 
739 const struct gfs2_glock_operations gfs2_rgrp_glops = {
740 	.go_sync = rgrp_go_sync,
741 	.go_inval = rgrp_go_inval,
742 	.go_instantiate = gfs2_rgrp_go_instantiate,
743 	.go_dump = gfs2_rgrp_go_dump,
744 	.go_type = LM_TYPE_RGRP,
745 	.go_flags = GLOF_LVB,
746 };
747 
748 const struct gfs2_glock_operations gfs2_freeze_glops = {
749 	.go_xmote_bh = freeze_go_xmote_bh,
750 	.go_demote_ok = freeze_go_demote_ok,
751 	.go_callback = freeze_go_callback,
752 	.go_type = LM_TYPE_NONDISK,
753 	.go_flags = GLOF_NONDISK,
754 };
755 
756 const struct gfs2_glock_operations gfs2_iopen_glops = {
757 	.go_type = LM_TYPE_IOPEN,
758 	.go_callback = iopen_go_callback,
759 	.go_dump = inode_go_dump,
760 	.go_flags = GLOF_LRU | GLOF_NONDISK,
761 	.go_subclass = 1,
762 };
763 
764 const struct gfs2_glock_operations gfs2_flock_glops = {
765 	.go_type = LM_TYPE_FLOCK,
766 	.go_flags = GLOF_LRU | GLOF_NONDISK,
767 };
768 
769 const struct gfs2_glock_operations gfs2_nondisk_glops = {
770 	.go_type = LM_TYPE_NONDISK,
771 	.go_flags = GLOF_NONDISK,
772 	.go_callback = nondisk_go_callback,
773 };
774 
775 const struct gfs2_glock_operations gfs2_quota_glops = {
776 	.go_type = LM_TYPE_QUOTA,
777 	.go_flags = GLOF_LVB | GLOF_LRU | GLOF_NONDISK,
778 };
779 
780 const struct gfs2_glock_operations gfs2_journal_glops = {
781 	.go_type = LM_TYPE_JOURNAL,
782 	.go_flags = GLOF_NONDISK,
783 };
784 
785 const struct gfs2_glock_operations *gfs2_glops_list[] = {
786 	[LM_TYPE_META] = &gfs2_meta_glops,
787 	[LM_TYPE_INODE] = &gfs2_inode_glops,
788 	[LM_TYPE_RGRP] = &gfs2_rgrp_glops,
789 	[LM_TYPE_IOPEN] = &gfs2_iopen_glops,
790 	[LM_TYPE_FLOCK] = &gfs2_flock_glops,
791 	[LM_TYPE_NONDISK] = &gfs2_nondisk_glops,
792 	[LM_TYPE_QUOTA] = &gfs2_quota_glops,
793 	[LM_TYPE_JOURNAL] = &gfs2_journal_glops,
794 };
795 
796